Hello guys,

I was just playing around with differential equations, when I noticed that symbolic solution is  different from the numerical.What is the reason for this strange behavior?

ODE := (diff(y(x), x))*(ln(y(x))+x) = 1

sol := dsolve({ODE, y(1) = 1}, y(x))

a := plot(op(2, sol), x = .75 .. 2, color = "Red");
sol2 := dsolve([ODE, y(1) = 1], numeric, range = .75 .. 2);

with(plots);
b := odeplot(sol2, .75 .. 2, thickness = 4);
display({a, b});

Strange_issue.mw

Mariusz Iwaniuk

Hello.

int(floor(x^2), x = 0 .. 2) = 6 , but it should be 1.85374.

Bug_in_integrate(floor_and_ceil).mw

Mariusz Iwaniuk

How to solve following recurrence equation:

a(0)=2;

a(n+1)=a(n)+a(n)^2

I tried,but it doesn't work.

How to find the sequence a_{n ?}

Maple_worsheet.mw

Mariusz Iwaniuk

I've got the following:

Integral_over_region.mw

M_Iwaniuk

>assume(x>0, n>0):int(x^n*ln(x)^n,x);

I_Mariusz